Good afternoon. I am going to present a research about the “ EFFECTS OF LAND USE ON THE ECOLOGICAL INTEGRITY OF HIGH-ALTITUDE ANDEAN STREAMS IN NORTHERN ECUADOR”. It is a work made with the collaboration of USFQ in Ecuador and UB in Spain.
Here we have a typical andean landscape. The effects of land use in streams are well know in the template zone but are not in the tropics. High altitude andean streams provide most of the water for cities and irrigation. In Ecuador, land use in these landscapes is growing without environmental planning.
Páramo streams in neotropical highlands are an unique ecosystems but also are the less studied. This streams have low water temperatures, low of oxygen saturation and low macroinvertebrate richness. In this scenario, we wanted to research which are the effects of land use in these streams?
We are interested in research three main objectives: The first one, is to analyze the effects of land use on the streams ecological integrity. The second, is to find which natural land cover is a better predictor of the streams ecological integrity. And finally, we are interested in develop future scenarios to do predictions of the streams ecological integrity.
We studied three catchments in the northeast of Ecuador, all these run to the pacific ocean. We divided the study area in two altitudes or ecosystems. The high altitude represents Páramo grassland located between 3500 and 4000 m asl. And the Evergreen mountain forest located between 2800 and 3000 m asl. We selected different land uses: reference, cattle, mine, urban settlements, trout production and car wash. For each land use site we sampled three streams (except trout production and car wash, that we didn’t have any repetition). In total we had twenty stream stations.
Here, the red line shows two altitudes, high altitude or páramo grassland and low altitude or evergreen mountain forest. The study area is important because is corridor between two National Ecological Reserves: Cayambe Coca and Antisana. Also is important for Ecuador because two pipes underground take drinking water for Quito and oil to the coast .
About the first objective, we worked in dry season, between September and December in 2009. In a 60 m transect. We collected qualitative macroinvertebrates samples with 5 Hess samples and 1 multihabitat sample We measured environmental variables. And also we measured two index of riparian vegetation and fluvial habitat.
Continuing with the fist objective, we designed two bentical integrity biotical index one for each altitude, and we called it IBI-Andean: First, we classified the streams in a gradient of human influence from low to high Second, we selected reference sites. Third, we calculate 20 metrics of richness, composition, tolerance/intorelance, feeding functional groups, habitat and dominance. Forth, we select the metrics that were sensible in discriminate reference and impairment sites. Fifth, we use quartile range decision rules with the selected metrics And finally, we calculated the index giving categories to the values and colors.
Also we calculate an integrity ecological index called Ecostriand. The index has two components: The riparian vegetation, that measures the percentage of cover, structure and quality of the vegetation. Plus the Andean biotic index that consist in a multihabitat sample of macroinvertebrates.
As results of our fist objective, the streams are grouped in altitudes, in red high altitude and in black low altitude. It is interesting that the variables that better explain this variation are riparian vegetation and conductivity.
Also as results of our fist objective, macroinvertebrate communities showed groups of streams classified by altitude HIHG AND LOW and by land use for example reference and urban settlements. The Chironomidae family was the typical taxa for all streams. Tricoptera and Ephemeroptera for high altitude and Ceratopogonidae, Tubificidae, Nematomorpha for low altitude.
The final results of our fist objective, is this map, where we determined the effects of land use on the streams integrity with the IBI-And index. Also we can compare this biotic index with the ecological integrity index, ECOSTRIAND. As we can see, several streams are matched up, this means that the IBI-And is quite good in classify the streams condition.
Cattle land use had a poor stream condition because the deforestation of riparian vegetation, canalization and extraction of water, and introduced grass cultivation.
Car wash and trout production had a poor and very poor stream condition because the high flows of wastewater, turbidly and contaminants.
Mines of material for construction had a poor stream condition because the high production of dust, low flows, turbidity and suspended sediments.
And urban settlements had a very poor stream condition because water extraction, diminution of flow, plastic garbage, and substrate with sediments and algae.
Summarizing this results: reference sites had a VERY GOOD stream condition, cattle, car was and mine POOR and trout production and urban settlements VERY POOR.
To analyze our second objective, we measured the natural land cover vegetation at three scales, reach, corridor and catchment. To measure the natural land cover at reach scale we used the QBR-And index, at corridor scales we used transects and at catchment scale we use GIS. We analyze the data with multiple regressions. The factors were the three scales and the response variables were biotic indexes and environmental parameters
The results show us, that reach scale is a better predictor of ecological integrity when we used the ecostriand variable.
Corridor scale is a better predictor of ecological integrity when we used the Richness and conductivity variable.
And, catchment scale is a better predictor of ecological integrity when we used the ABI, ECOSTRIAN and IBI-And variables. We used these three variables at catchment scale to work in our third objective.
About our third objective, it is an on going research. We use natural land cover at catchment scale to predict streams ecological integrity to the year of 2025 in three scenarios: RECUPERATION: it is the best scenario and will happen if natural vegetation increases ACTUAL TENDENCY: it is an scenario where the patron of lose of natural vegetation is the same since 1977 DEGRADATION: it is the worst scenario and will happen if the natural vegetation decreases in an accelerate way
The preliminary results about natural land cover Showed an advance of human influence comparing two historical moments from 1977 to 2001. By the year of 2025 natural land cover will be different depending of the recuperation, actual tendency and degradation scenarios. mbios espacio-temporales de la cobertura vegetal. Se muestran dos momentos históricos (1977 y 2001) y tres escenarios futuros (recuperación, tendencia actual y degradación) para el año 2025. Las proyecciones futuras se basan en matrices Markovianas de transición y procesos autómata celulares.
And here is an example of the streams condition based in land cover and temporal changes. Where te IBI-And in 1977 had a good condition, in 2010 has a poor condition and in 2025 will have a very poor condition acordin with the actual tendency scenario. IBI – zona alta Valores actuales y estimaciones según parámetros de regresión. Se modificaron los valores a nivel de cuenca según los escenarios analizados
As a conclusions:
Here we are! Thanks.
EFFECTS OF LAND USE ON THE ECOLOGICAL INTEGRITY OF HIGH-ALTITUDE ANDEAN STREAMS IN NORTHERN ECUADOR Ordóñez, V., Encalada, A., Ríos, B., Prat, N. and D. Vimos ALSO/NABS JUNE 2010 2 2
In every respect, the valley rules the stream (Hynes, 1975) We don't know much about streams and land use in tropical andean streams
P á ramo streams - Neotropical highlands Foto: E. Suárez
1. Land use and its effects on ecological integrity of the streams
2. Natural land cover spatial scales and ecological integrity
3. Predictions of the ecological integrity of the streams for future scenarios
Quito N Carihuaycu River Huarmihuaycu River Guambi River We studied three catchments in the northeast of Ecuador, South America Reference Land uses Cattle Mine Urban settlements *Trout production *Car wash Low Evergreen mountain forest 2800 – 3000 m asl High Páramo grassland 3500 – 4000 m asl Altitude
60 m transect 5 Hess (0,02m 2 ) 1 multihabitat (3min) Methods: 1. Ecological integrity O 2 , Temp, pH, flow, substratum, bacteria, PO 4 , NO 3 , SO 4 … Riparian vegetation (QBR-And), Fluvial habitat (IHF)
Methods: 1. Design of Biotic Index IBI-Andean 1 Classify streams in a gradient of human influence 2 Select references sites 3 Calculate 20 metrics 4 Select metrics 5 Use quartile range decision rules 6 Categories the metrics (names and colors)
ecological status river andean Methods: 1. ECOSTRIAND Index QBR-And index Riparian vegetation ABI - Andean Biotic Index Multihabitat, tolerance/intolerance, family level
Results: 1. Environmental variables showed groups of streams classified by altitude Euclidean distance Similarity 26% 62 % 34 % High altitude Low altitude
Results: 1. Macroinvertebrate communities showed groups of streams classified by altitude and land use High altitude Low altitude Bray Curtis Similarity 60 % Stress 0,18 Reference and cattle Urban settlement Reference and cattle Mine Trout production Car wash
N Good Very good Poor Very poor IBI-And Results: 1. Streams ecological integrity and land use ECOSTRIAND Low altitude High altitude
Cattle land use IBI-And “ Poor ” Deforestation riparian vegetation Canalization and water extraction Introduced grass
IBI-And “ Very Poor ” IBI-And “ Poor ” Trout production land use Car wash land use
Mine land use Dust IBI-And “ Poor ” Construction material
Urban settlements land use Low flow, sediments and algae Captations Garbage EII “ Very Poor ”
Results: 1. Streams ecological integrity and land use Land use IBI-And & Ecostrian Cattle, car wash and mine Poor Trout production and Urban settlements Very Poor Reference Very good
Methods: 2. Stream´s ecological integrity and spatial scales Reach QBR-And index Catchment GIS Corridor TRANSECTS Natural land cover vegetation Stream station
Results: 2. Natural land cover at reach scale ECOSTRIAND (riparian veg. + ABI) r 2 =0,62; F 3,11 =4,37; P= 0,0424
Results: 2. Natural land cover at corridor scale Richness Conductivity r 2 =0,97; F 3,7 =39,9; P= 0,0019 r 2 =0,95; F 3,7 =24,24; P= 0,005
Results: 2. Natural land cover at catchment scale ABI (tolerance/intolerance) ECOSTRIAND (riparian veg. + ABI) IBI-And r 2 =0,92; F 3,7 =14,99;P=0,012 r 2 =0,96; F 3,7 = 29,6; P= 0,003 r 2 =0,92; F 3,7 =17,33; P=0,009
Methods: 3. Three future scenarios for stream‘s ecological integrity Time (years) Natural land cover (km 2 ) 1977 2001 2025 Actual tendency Degradation Recuperation
Results: 3. Natural land cover 2001 2025 1977 Actual tendency Degradation Recuperation Natural vegetation Human influence
Results: 3. IBI-And predictiect in high altitude zone 1977 2010 2025 Actual tendency scenario Very good Good Poor Very poor